Postal Money Order versus Bank Money Order ???

USPS money orders are valid only within the U.S.

In favor of bank cashiers' checks, I recently sent one in payment for an overseas item, and the airmailed check never arrived. My bank was able to determine immediately whether the check had been cashed (had not been), placed a cancel payment on the check, and will return the money to my account. If the check had been cashed with a falsified signature, the money could probably have been recovered by arbitration between the issuing and paying banks. At least you get your $5 worth when it counts.

Bank money orders vary depending on the bank. My bank will cut me a money order for up to 1000 dollars. I've done this numerous times. After that, you have to either get more than one, or use a cashier's check. I don't get charged for any of them.

The USPS has 2 types of money orders, Domestic and International. They also have a limitation what countries the IMO's could be accepted at. For instance they won't issue one to Hong Kong and for the United Kingdom they only accept the US Domestic ones. These are my experiences as I always paid with these.

My banker told me it is possible to stop a certified check.

Beware of counterfeit Cashier's Checks. I have a friend who sold a used car, met the buyer at the seller's bank, deposited the buyer's bank-issued Cashiers Check for $9000 and then signed the car title over to the buyer. DAYS later the bank determined that the Cahiers Check was bogus and reversed the deposit. Problem was that the check looked so good that the seller and the bank did not notice anything wrong. Luckily for my friend, his insurance covered the loss, considered to be theft (by deception). Caveat Emptor. Bob